摘要:An inhibitor system composed of Poly(N-Methyl Aniline) [PNMANI] and histidine has been evaluated for its synergistic corrosion inhibition performance for mild steel in 0.5M H2SO4. PNMANI was prepared by free radical polymerisation using ammonium peroxodisulphate as initiator. 100ppm PNMANI exhibited 70% inhibition efficiency. In order to enhance the inhibitive action of PNMANI, histidine was added as a synergistic additive. The influence of histidine on PNMANI has been evaluated by weight loss and electrochemical methods. As expected, the inhibition efficiency gradually increased with increase in histidine concentration. The maximum inhibition efficiency of 89% was achieved for the inhibitor system viz 100ppm of PNMANI-130ppm of histidine. The enhanced inhibition performance of the inhibitor system has been proven thermodynamically.